Last Call Review of draft-ietf-isis-mi-bis-02
review-ietf-isis-mi-bis-02-genart-lc-levin-2017-04-13-00

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Document: draft-ietf-isis-mi-bis-02
Reviewer: Orit Levin
Review Date: 2017-04-06
IETF LC End Date: 2017-04-07
IESG Telechat date: 2017-04-13

Summary: This draft is "ready with issues" for publication.

Major issues: None.

Minor issues:

1. Add text explaining the reason (or reasons) for replacing the original RFC
6822 from 2012. Reason: It is a "bis" draft and there is no mention about it in
the text. 2. In Abstract, state clearly that this standard introduces the
support for instances vs. other already existing concepts also listed in the
Abstract (i.e., circuits, adjacencies,  topologies, etc.). Reason: The wording
is not clear about what is the new feature vs. what are the new benefits vs.
what was the original baseline 3. Throughout the document, use "standard
instance" instead of "IID = 0" or "IID #0". Reason: Expressions "standard
instance", "IID = 0" and "IID #0" are used interchangeably throughout the
document. It seems that they all refer to the same thing - the implementation
of the original protocol without the concept of instances. Please, correct me
if I am wrong. 4. In section 2 par 3, change "support" and "operates" to "MUST
support" to use requirements language. 5. In section 2 par 2, change "may" to
either "can" or "MAY" to clarify the intent. 6. In section 2.1 par 3, clarify
whether IID #0 is ever being used on the wire. Explain the concept of the
"standard interface" (see previous comment). Reason: It seems to me that IID #0
MUST never be used on the wire. Please, correct me if I am wrong. 7. In section
2.1, rephrase "marks ... by including" to "MUST include" to use requirements
language. 8. In section 2.4.1 par 2 second sentence, the sentence starting with
"However" needs to be rewritten using standards language to explain its intent.
9. In section 2.5, replace "exists" with "MUST be performed". 10. In section
2.5.1, replace "only operates" with "MUST only be performed". 11. In section
2.5.2, replace "This requires" with "It is REQUIRED". 12. In section 2.5.2
third sentence, after "inconsistent" insert "due to their configuration".
Please, correct me if I am wrong. 13. In section 7 Security Considerations,
discuss possible additional security considerations (or the lack of them)
related to the introduction of "instances". Reason: Beyond the normal IETF
procedure, this is especially important because "multiple instances allow
isolation of resources..." Can this isolation, if observed or interfered, be
damaging beyond the previous "standard interface" situation.

Nits/editorial comments:
1. Compare (Diff) the current draft with the published RFC 6822. You will find
that many of the editorial corrections got lost in the bis version. Omitted
corrections throughout the document include "instance-specific", " topology (or
topologies)", "Type-Length-Value" and others. 2. In Introduction par 4, either
change the two "may" to capitals or replace with "can" to clarify the intent.
3. In Introduction par 5, add references to where in the document the two
methods are described. Also, consider changing "defined" to "described". 4. In
Introduction par 7, move the last paragraph before listing the examples and
adjust the text accordingly, for clarity. 5. In section 2.3, replace "normal"
with "usual". 6. In section 2.6.1 first sentence, replace "not to cause" to "to
avoid".